Authors (including presenting author) :
Tang LM(1) , Woo KH(1), Wu CM(1), Siu HK(1), Gomersall C(2)
Affiliation :
(1)Physiotherapy Department, Prince of Wales Hospital, Hong Kong, (2)Department of Anaesthesia and Intensive Care, The Chinese University of Hong Kong
Introduction :
Patients on mechanical ventilator in intensive care units (ICUs) often suffer from various pulmonary dysfunctions. Chest physiotherapy using hyperinflation techniques have been shown to have positive effects on preventing and reversing atelectasis, and mobilizing peripheral secretions in ventilated patients. Ventilator hyperinflation (VHI) has demonstrated similar favorable effects on static lung compliance and secretion clearance when compared with manual hyperinflation (MHI) in previous studies. Moreover, there are some benefits of VHI over MHI, such as reduction of patient’s risk of derecruitment, and therapist’s exposure to air-borne or fluid-borne pathogens during circuit disconnecting when performing MHI. However, there is a lack of standardized protocols of VHI from current studies.
Objectives :
The purpose of this study is to compare the effectiveness of different VHI protocols on (1) improving static lung compliance, and (2) improving sputum clearance.
Methodology :
This study is a prospective, randomized crossover study. Patients admitted to the ICU of Prince of Wales Hospital were included if they were (i) mechanically ventilated with mode of ventilation in Pressure-Regulated Volume Control (PRVC) or Synchronized Intermittent Mandatory Ventilation (SIMV), (ii) Positive End-Expiratory Pressure lower than or equal to 10 cmH2O, (iii) peak inspiratory pressure (PIP) less than 30 cmH2O, (iv) diagnosed with respiratory failure and (v) were hemodynamically stable.
Patients received a randomized order of two different modes of treatment (treatment A and treatment B) on the same day, that lasted for three minutes each with 5-hour washout period in-between treatments. The intervention was aimed at 130% and 180% of the set tidal volume in treatment A and treatment B respectively. The change of static lung compliance between pre- and post-intervention was measured as the primary outcome, and sputum wet weight was the secondary outcome.
Result & Outcome :
In the period from August to November 2018, a total of five patients were recruited in this study. There was no statistically significant difference in static lung compliance and sputum wet weight between treatment A and B (2-way repeated measure ANOVA, p = 0.99). The results suggest that both treatment regimes provide similar treatment effects. However, treatment A may have an advantage with a lower set tidal volume, as this induces less increase in intrathoracic pressure, and may impose less disturbance to hemodynamic stability.
Co-location with:
